fix: resolve duplicate commit field and add commitId filter test

- Replace spread operator with explicit field selection to avoid
  duplicate commit field from getApks() and parseApkFilename()
- Add test case for commitId parameter filtering to ensure
  the filter parameter works correctly with new metadata extraction

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/api/apks/route.ts

@@ -21,7 +21,8 @@ export async function GET(request: Request) {
     const apksWithMetadata = apks.map(apk => {
       const parsed = parseApkFilename(apk.name);
       return {
-        ...apk,
+        name: apk.name,
+        size: apk.size,
         environment: parsed.environment,
         commit: parsed.commit,
         modifiedAt: apk.modifiedAt.toISOString(),